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C# C# Objects Loops and Final Touches For Loops

Cannot use operand "+=" for the frog code challenge for some reason

FrogStats.cs(11,17): error CS0019: Operator +=' cannot be applied to operands of typedouble' and `Treehouse.CodeChallenges.Frog' That is the error I am getting.

I tried using + just to test and it seems like any operand I use causes an error.

Not sure what I am doing wrong

FrogStats.cs
namespace Treehouse.CodeChallenges
{
    class FrogStats
    {
        public static double GetAverageTongueLength(Frog[] frogs)
        {   double result;
            int num = frogs.Length;

            for(int i=0; i< frogs.Length; i++)
            {
                result += frogs[i];
            }
            result /= num;

            return result;
        }
    }
}
Frog.cs
namespace Treehouse.CodeChallenges
{
    public class Frog
    {
        public int TongueLength { get; }

        public Frog(int tongueLength)
        {
            TongueLength = tongueLength;
        }
    }
}

1 Answer

Steven Parker
Steven Parker
231,198 Points

The "preview" button error message is telling you that you're trying to add the frog itself, so instead use just the TongueLength:

                result += frogs[i].TongueLength;

The other issue is that you cannot use the '+=' operator on variables that haven't been initialized (only declared), so give "result" an initial value:

            double result = 0;

Thank you very much that solved it!.